Comparison of screening methods to evaluate the response of St. Augustine grass to Magnaporthe oryzae Academic Article uri icon


  • The objective of this study was to develop a reliable and high throughput screening method to evaluate the response of St. Augustine grass (Stenotaphrum secundatum) genotypes to the grey leaf spot (GLS) caused by Magnaporthe oryzae infection. Whole plant, detached stolon and detached leaf assays under growth chamber conditions were compared to field conditions on eight commercial and nine advanced breeding lines of St. Augustine grass. Disease was assessed using two variables, lesion size (LS) and overall plant disease severity (SEV). LS and SEV were highly correlated for field and growth chamber screening methods using the whole plant assay (LS r 2 =079; SEV r 2 =083; P0001), the detached stolon assay (LS r 2 =075; SEV r 2 =072; P0001), and the detached leaf assay (LS r 2 =046; SEV r 2 =060; P0001). Genotypic variation for resistance in 17 St. Augustine grass genotypes was identified using all screening methods for LS (P<005) and SEV (P<005). The rank-sum method was used to classify St. Augustine grass genotypes into highly resistant (HR), resistant (R), moderately resistant (MR), moderately susceptible (MS), susceptible (S) and highly susceptible (HS) classes based on the rank-sum values of LS and SEV. Two introduced African polyploids used as parents, and two F 1 interploid progeny obtained using an in vitro embryo rescue technique, were classified as highly resistant (HR), or resistant (R), across all screening methods. 2011 The Authors. Plant Pathology 2011 BSPP.

published proceedings


altmetric score

  • 3

author list (cited authors)

  • Metz, S. P., Chandra, A., Genovesi, A. D., & Campos, C. F.

citation count

  • 6

complete list of authors

  • Metz, SP||Chandra, A||Genovesi, AD||Campos, CF

publication date

  • April 2012